Numerical Analysis of Flow Distribution Inside a Fuel Assembly with Split-Type Mixing Vanes

Title & Authors
Numerical Analysis of Flow Distribution Inside a Fuel Assembly with Split-Type Mixing Vanes
Lee, Gong Hee; Cheong, Ae Ju;

Abstract
As a turbulence-enhancing device, a mixing vane, which is installed at a spacer grid of the fuel assembly, plays an important role in improving convective heat transfer by generating either swirl flow in the subchannels or cross flow between the fuel rod gaps. Therefore, both the geometric configuration and the arrangement pattern of a mixing vane are important factors in determining the performance of a mixing vane. In this study, in order to examine the flow-distribution features inside a $\small{5{\times}5}$ fuel assembly with split-type mixing vanes, which was used in the benchmark calculation of the OECD/NEA, we conduct simulations using the commercial computational fluid dynamics software, ANSYS CFX R.14. We compare the predicted results with measured data obtained from the MATiS-H (Measurement and Analysis of Turbulent Mixing in Subchannels-Horizontal) test facility. In addition, we discuss the effect of the split-type mixing vanes on the flow pattern inside the fuel assembly.
Keywords
Computational Fluid Dynamics;Mixing Vane;Rod Bundle;Split-type;Subchannel;Turbulent Flow;
Language
Korean
Cited by
References
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